For quick relief on the spot, try the 5‑minute “cyclic sigh”: two inhalations followed by a prolonged exhalation

Cost: No cost at all. Just 5 minutes a day.
In plain terms: In a one‑month controlled trial where participants performed each of three breathing exercises for 5 minutes daily, all three proved more effective than an equal amount of mindfulness meditation at lifting mood and lowering respiratory rate. The “cyclic sigh” — which emphasizes lengthening the exhale — performed best. The method is simple: inhale once through the nose, then take a brief second inhale to fully fill the lungs, and finally exhale slowly through the mouth. This particular study relied on self‑reported data and involved a relatively small group of volunteers, yet it required zero expense.
Benefit: This home‑based, randomized controlled trial compared three distinct 5‑minute daily breathing routines — cyclic sighing (focused on extended exhalation), box breathing (equal durations of inhale, hold, and exhale), and cyclic hyperventilation with pauses — against an equivalent mindfulness meditation regimen over a month. Using a mixed‑effects model on pooled data, each breathing technique outperformed meditation; cyclic sighing stood out for its superior impact on mood improvement (statistically significant at P<0.05) and on reducing breathing frequency (also P<0.05).
Evidence grade: B
Sources:Balban MY, Neri E, Kogon MM, et al. (2023). Brief structured respiration practices enhance mood and reduce physiological arousal. Cell Reports Medicine, 4(1), 100895. https://doi.org/10.1016/j.xcrm.2022.100895
Notes: Execute the exercise by inhaling once through the nose, briefly adding a second inhale to maximize lung expansion, then exhale gently and fully through the mouth for a full 5 minutes. Although this trial was conducted at home, relied on participant self‑assessment, and involved a modest sample size, its benefits are clear: it costs nothing, takes only five minutes, can be done anywhere, and offers modest but tangible advantages over standard mindfulness practice.